1. Field
This disclosure relates to fuse-based cells, more particularly to those fuse-based cells programmable with high voltages.
2. Background
Fuse-based cells have many applications in semiconductor device manufacture. The cells can permanently store data, for example, where a burned fuse represents a “1” and an unburned fuse represents a “0.” Similarly, fuses can form permanent connections on integrated circuits after they are manufactured. A sensing circuit typically determines the state of the fuse. These sensing circuits typically detect a change in the resistance of the fuse device from a low value for unburned fuses to a high value for burned fuses.
However, advances in semiconductor manufacturing technology have decreased the resistance of fuses after they have been burned, referred to as post-burn resistance. Similarly, the operating voltages of most semiconductor devices have been reduced in pursuit of lower power consumption. While higher burning voltages move the post-burn resistance to a high level, the higher voltages may damage semiconductor devices designed to operate at lower voltages.
Therefore, it would be useful to have the ability to use higher burning voltages for fuse-based devices, while providing protection for devices that operate at lower voltages.